Lamp base



FIG. 1 is a perspective view of a lamp base showing our new design;

FIG. 2 is a top plan view thereof on an enlarged scale;

FIG. 3 is a front elevational view thereof on an enlarged scale, the rear being identical;

FIG. 4 is a side elevational view thereof on an enlarged scale, the opposite side being identical.

The broken line representation of a lamp shade and lamp poles are for illustrative purposes only. 

The ornamental design for a lamp base, as shown and described. 